Prince Charles said he did not want to hand on 'a total poisoned chalice' to future generations. Photograph: Chris Jackson/Getty Images

The Prince of Wales has spoken about how the prospect of becoming a grandfather is spurring his environmental beliefs, saying he does not want to "hand on an increasingly dysfunctional world".

Charles, who has long campaigned on environmental issues, told ITV's This Morning that he did not want the Duke and Duchess of Cambridge's child, due to be born next summer, to ask him why he had not done more to tackle issues such as climate change.

In an interview at Clarence House with presenters Phillip Schofield and Holly Willoughby, to be broadcast on Monday, he said: "I've gone on for years about the importance of thinking about the long term in relation to the environmental damage, climate change and everything else.

"We don't, in a sensible world, want to hand on an increasingly dysfunctional world to our grandchildren, to leave them with the real problem.

"I don't want to be confronted by my future grandchild and [have] them say: 'Why didn't you do something?' So clearly now that we will have a grandchild, it makes it even more obvious to try and make sure we leave them something that isn't a total poisoned chalice."

Charles spoke as he backed This Morning's You Can Be Heroes Week, which aims to capitalise on the success of the 2012 Olympic and Paralympic Games and create a new army of volunteers across the UK.

He said in December he was "thrilled" at the prospect of becoming a grandfather, after William and Kate announced the duchess was expecting their first child. She spent three days in the private King Edward VII's hospital in London being treated for a severe form of morning sickness.

Charles has been a strong advocate of taking action to protect the environment for many years. In 2007, he set up The Prince's Rainforest Group to find a solution to save the world's threatened forests. He addressed a UN international climate summit in Copenhagen in 2009 and the following year gave a keynote speech to the Oslo climate and forest conference.

In a wide-ranging interview with the ITV daytime show, he also reiterated his worry about Prince Harry, who is serving in Afghanistan, something he also did at the "Millies" military awards last month.

"If you are a parent or relation to a loved one and that person is away in these incredibly dangerous and challenging circumstances, I know you worry all the time," he said.

"Certainly every night I worry. But he [Prince Harry] loves doing what he is doing and he is brilliant at it."

He added: "I constantly meet the families of those who have lost their sons, husbands, brothers or sisters … and I have some understanding at least of what they go through."

Backing the programme's campaign supporting volunteering he said events such as the 2012 Olympics, Paralympics and diamond jubilee "bring out the best in people".

An army of much-hailed volunteer "games makers" was created for the Olympics and Paralympics, helping events at the many venues run smoothly in their distinctive uniforms.

"A lot of people don't realise how so many of these people keep the whole show on the road," said.

"There is something remarkable in this country, I think, about the volunteering spirit."

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